Merge branch 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull uaccess unification updates from Al Viro:
 "This is the uaccess unification pile. It's _not_ the end of uaccess
  work, but the next batch of that will go into the next cycle. This one
  mostly takes copy_from_user() and friends out of arch/* and gets the
  zero-padding behaviour in sync for all architectures.

  Dealing with the nocache/writethrough mess is for the next cycle;
  fortunately, that's x86-only. Same for cleanups in iov_iter.c (I am
  sold on access_ok() in there, BTW; just not in this pile), same for
  reducing __copy_... callsites, strn*... stuff, etc. - there will be a
  pile about as large as this one in the next merge window.

  This one sat in -next for weeks. -3KLoC"

* 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (96 commits)
  HAVE_ARCH_HARDENED_USERCOPY is unconditional now
  CONFIG_ARCH_HAS_RAW_COPY_USER is unconditional now
  m32r: switch to RAW_COPY_USER
  hexagon: switch to RAW_COPY_USER
  microblaze: switch to RAW_COPY_USER
  get rid of padding, switch to RAW_COPY_USER
  ia64: get rid of copy_in_user()
  ia64: sanitize __access_ok()
  ia64: get rid of 'segment' argument of __do_{get,put}_user()
  ia64: get rid of 'segment' argument of __{get,put}_user_check()
  ia64: add extable.h
  powerpc: get rid of zeroing, switch to RAW_COPY_USER
  esas2r: don't open-code memdup_user()
  alpha: fix stack smashing in old_adjtimex(2)
  don't open-code kernel_setsockopt()
  mips: switch to RAW_COPY_USER
  mips: get rid of tail-zeroing in primitives
  mips: make copy_from_user() zero tail explicitly
  mips: clean and reorder the forest of macros...
  mips: consolidate __invoke_... wrappers
  ...

2 files changed, 34 insertions, 127 deletions

diff --git a/include/asm-generic/extable.h b/include/asm-generic/extable.h
new file mode 100644
index 000000000000..ca14c6664027
--- /dev/null
+++ b/include/asm-generic/extable.h
@@ -0,0 +1,26 @@
+#ifndef __ASM_GENERIC_EXTABLE_H
+#define __ASM_GENERIC_EXTABLE_H
+
+/*
+ * The exception table consists of pairs of addresses: the first is the
+ * address of an instruction that is allowed to fault, and the second is
+ * the address at which the program should continue.  No registers are
+ * modified, so it is entirely up to the continuation code to figure out
+ * what to do.
+ *
+ * All the routines below use bits of fixup code that are out of line
+ * with the main instruction path.  This means when everything is well,
+ * we don't even have to jump over them.  Further, they do not intrude
+ * on our cache or tlb entries.
+ */
+
+struct exception_table_entry
+{
+	unsigned long insn, fixup;
+};
+
+
+struct pt_regs;
+extern int fixup_exception(struct pt_regs *regs);
+
+#endif
diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h
index cc6bb319e464..bbe4bb438e39 100644
--- a/include/asm-generic/uaccess.h
+++ b/include/asm-generic/uaccess.h
@@ -6,7 +6,6 @@
  * on any machine that has kernel and user data in the same
  * address space, e.g. all NOMMU machines.
  */
-#include <linux/sched.h>
 #include <linux/string.h>
 
 #include <asm/segment.h>
@@ -35,9 +34,6 @@ static inline void set_fs(mm_segment_t fs)
 #define segment_eq(a, b) ((a).seg == (b).seg)
 #endif
 
-#define VERIFY_READ	0
-#define VERIFY_WRITE	1
-
 #define access_ok(type, addr, size) __access_ok((unsigned long)(addr),(size))
 
 /*
@@ -52,87 +48,6 @@ static inline int __access_ok(unsigned long addr, unsigned long size)
 #endif
 
 /*
- * The exception table consists of pairs of addresses: the first is the
- * address of an instruction that is allowed to fault, and the second is
- * the address at which the program should continue.  No registers are
- * modified, so it is entirely up to the continuation code to figure out
- * what to do.
- *
- * All the routines below use bits of fixup code that are out of line
- * with the main instruction path.  This means when everything is well,
- * we don't even have to jump over them.  Further, they do not intrude
- * on our cache or tlb entries.
- */
-
-struct exception_table_entry
-{
-	unsigned long insn, fixup;
-};
-
-/*
- * architectures with an MMU should override these two
- */
-#ifndef __copy_from_user
-static inline __must_check long __copy_from_user(void *to,
-		const void __user * from, unsigned long n)
-{
-	if (__builtin_constant_p(n)) {
-		switch(n) {
-		case 1:
-			*(u8 *)to = *(u8 __force *)from;
-			return 0;
-		case 2:
-			*(u16 *)to = *(u16 __force *)from;
-			return 0;
-		case 4:
-			*(u32 *)to = *(u32 __force *)from;
-			return 0;
-#ifdef CONFIG_64BIT
-		case 8:
-			*(u64 *)to = *(u64 __force *)from;
-			return 0;
-#endif
-		default:
-			break;
-		}
-	}
-
-	memcpy(to, (const void __force *)from, n);
-	return 0;
-}
-#endif
-
-#ifndef __copy_to_user
-static inline __must_check long __copy_to_user(void __user *to,
-		const void *from, unsigned long n)
-{
-	if (__builtin_constant_p(n)) {
-		switch(n) {
-		case 1:
-			*(u8 __force *)to = *(u8 *)from;
-			return 0;
-		case 2:
-			*(u16 __force *)to = *(u16 *)from;
-			return 0;
-		case 4:
-			*(u32 __force *)to = *(u32 *)from;
-			return 0;
-#ifdef CONFIG_64BIT
-		case 8:
-			*(u64 __force *)to = *(u64 *)from;
-			return 0;
-#endif
-		default:
-			break;
-		}
-	}
-
-	memcpy((void __force *)to, from, n);
-	return 0;
-}
-#endif
-
-/*
  * These are the main single-value transfer routines.  They automatically
  * use the right size if we just have the right pointer type.
  * This version just falls back to copy_{from,to}_user, which should
@@ -171,8 +86,7 @@ static inline __must_check long __copy_to_user(void __user *to,
 
 static inline int __put_user_fn(size_t size, void __user *ptr, void *x)
 {
-	size = __copy_to_user(ptr, x, size);
-	return size ? -EFAULT : size;
+	return unlikely(raw_copy_to_user(ptr, x, size)) ? -EFAULT : 0;
 }
 
 #define __put_user_fn(sz, u, k)	__put_user_fn(sz, u, k)
@@ -187,28 +101,28 @@ extern int __put_user_bad(void) __attribute__((noreturn));
 	__chk_user_ptr(ptr);					\
 	switch (sizeof(*(ptr))) {				\
 	case 1: {						\
-		unsigned char __x;				\
+		unsigned char __x = 0;				\
 		__gu_err = __get_user_fn(sizeof (*(ptr)),	\
 					 ptr, &__x);		\
 		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
 		break;						\
 	};							\
 	case 2: {						\
-		unsigned short __x;				\
+		unsigned short __x = 0;				\
 		__gu_err = __get_user_fn(sizeof (*(ptr)),	\
 					 ptr, &__x);		\
 		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
 		break;						\
 	};							\
 	case 4: {						\
-		unsigned int __x;				\
+		unsigned int __x = 0;				\
 		__gu_err = __get_user_fn(sizeof (*(ptr)),	\
 					 ptr, &__x);		\
 		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
 		break;						\
 	};							\
 	case 8: {						\
-		unsigned long long __x;				\
+		unsigned long long __x = 0;			\
 		__gu_err = __get_user_fn(sizeof (*(ptr)),	\
 					 ptr, &__x);		\
 		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
@@ -233,12 +147,7 @@ extern int __put_user_bad(void) __attribute__((noreturn));
 #ifndef __get_user_fn
 static inline int __get_user_fn(size_t size, const void __user *ptr, void *x)
 {
-	size_t n = __copy_from_user(x, ptr, size);
-	if (unlikely(n)) {
-		memset(x + (size - n), 0, n);
-		return -EFAULT;
-	}
-	return 0;
+	return unlikely(raw_copy_from_user(x, ptr, size)) ? -EFAULT : 0;
 }
 
 #define __get_user_fn(sz, u, k)	__get_user_fn(sz, u, k)
@@ -247,36 +156,6 @@ static inline int __get_user_fn(size_t size, const void __user *ptr, void *x)
 
 extern int __get_user_bad(void) __attribute__((noreturn));
 
-#ifndef __copy_from_user_inatomic
-#define __copy_from_user_inatomic __copy_from_user
-#endif
-
-#ifndef __copy_to_user_inatomic
-#define __copy_to_user_inatomic __copy_to_user
-#endif
-
-static inline long copy_from_user(void *to,
-		const void __user * from, unsigned long n)
-{
-	unsigned long res = n;
-	might_fault();
-	if (likely(access_ok(VERIFY_READ, from, n)))
-		res = __copy_from_user(to, from, n);
-	if (unlikely(res))
-		memset(to + (n - res), 0, res);
-	return res;
-}
-
-static inline long copy_to_user(void __user *to,
-		const void *from, unsigned long n)
-{
-	might_fault();
-	if (access_ok(VERIFY_WRITE, to, n))
-		return __copy_to_user(to, from, n);
-	else
-		return n;
-}
-
 /*
  * Copy a null terminated string from userspace.
  */
@@ -348,4 +227,6 @@ clear_user(void __user *to, unsigned long n)
 	return __clear_user(to, n);
 }
 
+#include <asm/extable.h>
+
 #endif /* __ASM_GENERIC_UACCESS_H */